Disk drives typically store data on magnetic and/or optical storage media which rotates about a central axis. This rotation creates airflow within the disk drive having both radial and axial velocities, which in turn produces a pressure gradient near the outer disk edge. As disk rotation speeds increase, the resulting rotation-induced airflow tends to increase undesirable disk flutter.
In addition to disk flutter, rotation-induced airflow also tends to move particles that may enter the microscopic space between the disk drive's read/write head(s) and the disk surface(s), thereby resulting in possible component damage or read/write errors. To avoid this, recirculation filters may be oriented near the outer disk edge in the path of the airflow in order to filter out particles which become airborne during disk drive operation. Since filtration efficiency is direct related to disk performance and longevity, there is a need for a disk drive design which improves filtration efficiency by improving the airflow characteristics of disk drives.